---
title: 'FAQ'
description: 'Common questions and answers about Nile Auth'
---

## General Questions

### What is Nile Auth?

Nile Auth is a multi-tenant authentication service that provides authentication and authorization features for multi-tenant applications.
This service ensures secure, scalable authentication while maintaining tenant isolation.
All B2B applications are multi-tenanted, and they all have concepts of tenants, users and data. Nile Auth brings these together
in a single service - authenticating users, managing tenants and access to their data.

### How is Nile Auth different from other auth providers?

- Nile Auth is purpose-built for multi-tenanted applications. It provides per-tenant authentication, authorization and user management.
- Nile Auth is an open source service - you can self-host it or use our hosted service
- Both managed and self-hosted options store all user data in your own database.
- Nile Auth supports a wide range of frameworks
- Nile Auth has beautiful and flexible UI components

## Technical Questions

### How does tenant isolation work?

The short answer is that Nile separates tenant's data by isolating each tenant into a virtual database - separate blocks in memory and on disk.
By default, all tenants share the same compute resources (CPU, memory, etc), but you can also provision dedicated compute resources for a subset of tenants.

When a user authenticates, Nile Auth is aware of the tenants the user belongs to and can enforce access to data based on the
user's tenant membership. Nile also handles the routing of each user's queries to the correct tenant's database.

This is just at the high level. You can read more about it in the [tenant isolation](/tenant-virtualization/tenant-isolation) documentation.

### Can I use Nile Auth with my existing database?

Yes, Nile Auth can be configured to use your existing database.

### How do I implement SSO?

SSO is not yet supported, but it is planned for the future.

## Security

### How does Nile Auth handle security?

Nile Auth uses industry standard security best practices. All communication is encrypted using TLS, all stored data is encrypted at rest.
Nile Auth enforces secure, http-only cookies to prevent cross-site scripting attacks. It uses CSRF tokens to prevent cross-site request forgery.
Whenever possible, Nile Auth sessions are stored in the database, where they can be inspected and revoked if needed.
You can read more about our use of [cookies](/auth/concepts/cookies), [jwt](/auth/concepts/jwt), [oauth](/auth/concepts/oauth) and [sessions](/auth/concepts/sessions).

At the database layer, security is enforced by Nile's virtual tenant databases and the isolation they provide.

## Pricing and Plans

### Is there a free tier?

Yes, we offer a generous free tier - with unlimited databases and users. You can see all the details on our [pricing page](https://www.thenile.dev/pricing).

### How does Nile Auth compare to other auth providers?

We literally give away authentication for free - you have unlimited tenants and unlimited users available in every pricing tier - including the free tier.

### What are the usage limits?

There are none. Everything is unlimited - tenants, users, databases.

### Which frameworks are supported?

We are adding new frameworks fast. For starters, we support Next.js, Express, React, Remix, and more.
Check the [frameworks](/auth/frameworks/express) pages for the latest information.

### Can I self-host Nile Auth?

Yes, you can self-host Nile Auth. We provide a docker image and a helm chart.
And of course, it is open source, so you can build and deploy it in any way you want.

### Where can I get help?

- [Error Reference](/auth/help/errors)
- [Join our Community](/auth/help/community)
- [Contact Support](https://www.thenile.dev/contact-us)
